x86: Add asm/elf.h for x86-specific ELF definitions

Bring in this file from Linux 4.1. It supports relocation features specific
to x86.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/include/asm/elf.h

+/*
+ * Brought in from Linux 4.1, removed things not useful to U-Boot.
+ * The definitions perhaps came from the GNU Library which is GPL.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _ASM_X86_ELF_H
+#define _ASM_X86_ELF_H
+
+/* ELF register definitions */
+#define R_386_NONE	0
+#define R_386_32	1
+#define R_386_PC32	2
+#define R_386_GOT32	3
+#define R_386_PLT32	4
+#define R_386_COPY	5
+#define R_386_GLOB_DAT	6
+#define R_386_JMP_SLOT	7
+#define R_386_RELATIVE	8
+#define R_386_GOTOFF	9
+#define R_386_GOTPC	10
+#define R_386_NUM	11
+
+/* x86-64 relocation types */
+#define R_X86_64_NONE		0	/* No reloc */
+#define R_X86_64_64		1	/* Direct 64 bit  */
+#define R_X86_64_PC32		2	/* PC relative 32 bit signed */
+#define R_X86_64_GOT32		3	/* 32 bit GOT entry */
+#define R_X86_64_PLT32		4	/* 32 bit PLT address */
+#define R_X86_64_COPY		5	/* Copy symbol at runtime */
+#define R_X86_64_GLOB_DAT	6	/* Create GOT entry */
+#define R_X86_64_JUMP_SLOT	7	/* Create PLT entry */
+#define R_X86_64_RELATIVE	8	/* Adjust by program base */
+/* 32 bit signed pc relative offset to GOT */
+#define R_X86_64_GOTPCREL	9
+#define R_X86_64_32		10	/* Direct 32 bit zero extended */
+#define R_X86_64_32S		11	/* Direct 32 bit sign extended */
+#define R_X86_64_16		12	/* Direct 16 bit zero extended */
+#define R_X86_64_PC16		13	/* 16 bit sign extended pc relative */
+#define R_X86_64_8		14	/* Direct 8 bit sign extended  */
+#define R_X86_64_PC8		15	/* 8 bit sign extended pc relative */
+
+#define R_X86_64_NUM		16
+
+#endif